Evaluation of 308-nm monochromatic excimer light in the treatment of psoriasis vulgaris and palmoplantar psoriasis

Background: The purpose of this study is to evaluate the efficacy and safety of 308‐nm monochromatic excimer light (MEL) in the treatment of psoriasis vulgaris and palmoplantar psoriasis. Methods: Thirty‐five patients with psoriasis vulgaris and 15 patients with palmoplantar psoriasis were recruited for this study. Thirty patients with psoriasis vulgaris completed a total of 16 treatments with 308‐nm MEL twice a week, and 15 patients palmoplantar psoriasis completed 25 treatments administered once weekly. The clinical response to therapy and adverse effects were recorded. Results: Patients with psoriasis vulgaris (n=30) showed a 74.6% improvement in the mean psoriasis area and severity index score after a total of 16 MEL treatments (2 ×/week) with 36.7% of the patients (n=11) achieving clearance. Patients with palmoplantar psoriasis (n=15) showed a 52.5% improvement in the mean severity index score after a total of 25 MEL treatments (1 ×/week) with only one patient (6.7%) achieving clearance. The MEL therapy was well tolerated with a low incidence of side effects, which included pruritus, erythema and blister formation. Conclusion: The 308‐nm MEL can be utilized as an effective and safe treatment modality for patients with mild‐to‐moderate psoriasis vulgaris and palmoplantar psoriasis.